Core disintegrating drilling tool



2 SHEETS-Si-IEET 1 A. ARUTUNOFF INVENTOR.

CORE DISINTEGRATING DRILLING TOOL Nov. 25, 1952 Filed Jan. 2, 1952 1952 A. ARUTUNOFF com: DISINTEGRATING DRILLING TOOL 2 SHEETS-SHEET 2 Filed Jan. 2, 1952 Arma zls'Aru Zane/7 Patented Nov. 25, 1952 UNI-TED STATES PATENT OFFICE CORE DISINTEGRATING DRILLING TOOL Armais Arutunoff, Bartlesville, Okla;

Application January 2, 1952; Serial No.- 264,520

14.0laims. l.

Thisinventionrelates to a rotary rockdrillingibit and more particularly a diamond-studded bit having a maincutting-head provided with a supplemental core-removing or disintegrating bit.-

Ordinarily, diamond bits used in connection with hard rock drilling operations by'the rotary method are limited in their penetrating speed by the core 'ofrockwhich forms-in the central portion of the hole. The lack of-cutting speed at the center ofv the rotary bit materially retardsthe operation-because the rock core in the central portion is. not actually cutbut must be crushed by-the weight on the bit before progress-is possible. It is, therefore,,the object ofmy invention to provide arotary bit having a-main cutting-head of the type which provides a central core-receiving recess at its cutting end and is provided with asupplemental core-removing bit so arranged with respect to-the core receiving-recess as to disintegrate the core as the main cutting head progresses.

Another objectof my invention is to provide a self-contained drilling tool wherein the supplementalcore-removing bit is driven by afiuidoperated motor housed in the main body structure which-supports the cutting head.

Awfurther' object of the invention isto provide a rotary bit equipped with a fluid operated supplemental core-removing bit, wherein the fluid employed foroperating the. motor is utilizedas a flushing medium in disposing of'the cuttings.

Still another object of the invention is to provide. a relatively simple. cutting, unit which is compact and sturdy in construction. and one whichmay easily be assembled and. dismantled for purposes of'cleaning and repairs.

With the above and otherobjectsin viewwhich will appear as the description proceed's,.my invention consists in the novel features herein set forth, illustrated in the accompanying drawings, anl' more particularly. pointed out in the appended claims.

Referring to the drawings in which numerals of like character designate similar parts throughout the several views,

Figure 1 isa longitudinal sectional view of myv improvedbit;

Figure 2 is a bottom end'view of. the diamond bit or main cutting head;

Figure 3 be transverse sectional view taken on line 3--3 of Figure 1 Figure 4 is a similar sectional view'taken on line 4-4 of Figure 1;,and

Figurefiis a'transverse.sectionalview takenon ery of the cylindrical body 8.

line 5-5 of Figure 1, showing the overlapping relationship of the supplemental bit and the core-receiving recess of the main cutting head.

In the drawings,.referring first to Figure 1, 5 represents the base portion of a' hollow cylindrical shank'or coupling member, reduced and threaded as at 6- to facilitate connection to the usualhollow drill. stem" (not shown). The cylindrical base portion 5 of the shank is recessed and internally threaded as at T to receive complementary threads at the upper end of a cylindrical body 8- which serves both as a housing for: a fluid-operated motor. and as'a supporting member for the main cuttinghead as will hereinafter appear.

The lower end of the body 8' is-reduced' and threadedas at 9 to engagecomplementary internal threads on the upstanding connecting flange of the main'cutting head ID, the cutting portionzof which is preferably diamond-studded and extends radially slightly beyond the periph- The central portionofthecutting head I0 is recessed as at H, to form an annular cutting areawhich is preferably divided into-a series of segmental cutting units. l2byan intervening series of channels l3 which radiate from and communicatewith the central recess H. A-s' seen in Figuresl and 2,

each of these channels extends entirely around thecutting surface of the'head 10, so as to establish free communication from thercentral recess H to the periphery of thehead.

Turning to Figure 4, the central portion of the body 8 is provided with a cavity I4 which is substantially elliptical in cross section, for receiving apair of elongated" gears l5 and it, which are longitudinally arranged in'meshing relation and rotatably supported between upper and lower end endplate l8 and the interior of the main cutting head 10 andextends radially beyond the corereceiving recess H in the latter. Thesupplementalbit 28 and'its supporting spindle l9 are arranged eccentrically with respect to the axis pore-receivingrecess H, as seenin Figure 1, and

its peripheral boundary overlaps the central portion of the core-receiving recess.

In order to take up the vertical thrust of the supplemental bit, the upper spindle 22 of the gear I is provided with a thrust bearing 23, disposed in an enlarged opening in the upper end plate H, which opening may be provided with an inset, adjustable, threaded cover 24.

As best seen in Figures 3 and 4, the gear motor formed in the body 8 has an elongated fluid inlet passage 25 on one side which opens through the end plate I! and communicates at its upper end with the central passageway 26 in the shank 5. On the opposite side is provided an elongated fluid discharge passage 21 opening through end plate 18 and communicating at its lower end with the transverse recess 2|. Thus, when fluid is forced from the drill stem and shank 5 into the inlet passage 25 on one side of the meshing gears I5 and [6, the gears are caused to revolve re- "spectively in opposite directions, the gear rotating the supplemental bit 20. As the gears rotate the driving fluid passes with them and enters the discharge passage 21 from whence it is discharged into the transverse recess 2| at the lower end of the body 8. The discharged fluid thus flows over the core in recess l l and through the several channels [3 between the cutting units l2, carrying with it all of the cuttings which are then forced to the surface.

It will be apparent that during this operation the main body 8 and cutting head It] are continuously rotated by the stem attached to the shank 5, and as the cutting head turns, the axis of the simultaneously rotating supplemental bit follows a circular path which continuously overlies the core forming in the central recess l I. Thus, the core is constantly disintegrated by the bit 20 as the main cutting head progresses.

In the designing of my improved cutting unit the dimensions of the various parts are proportioned with due regard to the amount of circulating fluid necessary to carry the cuttings as well as an optimum surface speed of rotation of the grinding wheel 20. If the gears l5, l6 are of insufficient length, the speed of rotation may become too high for economical utilization of the life of the diamonds on the grinding wheel and therefore the gears should be sufficiently long for the surface speed of the grinding wheel to be only slightly greater than the surface speed of the periphery of the main cutting head It] when a normalamount of fluid is being circulated through the motor.

It will thus be seen that I have provided a relatively simple self-contained drilling tool which is sturdy in construction, efficient and positive in operation, and easily assembled and dismantled for purposes of cleaning and repair. The novel arrangement of the eccentric supplemental bit which constantly overlies the core and is operated by the same fluid utilized to wash away the cuttings, causes a progressive disintegration of the core without the necessity of withdrawing the drill head from the hole to remove the core whenever the core barrel becomes full.

From the foregoing it is believed that my invention may be readily understood by those skilled in the art without further description, it being borne in mind that numerous changes may be made in the details of construction without departing from the spirit of the invention as set forth in the following claims. For example, while the drawings illustrate this device as embodying a single supplemental bit 20 mounted on the extension of gear 15, it will be understood that I may also employ an additional supplemental bit on the extension of the companion gear I8.

I claim:

1. A rotary bit comprising a connecting shank, a cylindrical body secured to said shank and depending therefrom, a main cutting head carried by the lower extremity of said body and having a central core-receiving recess at its cutting end, forming an annular cutting portion, a chamber in said body, housing a fluid-actuated motor, a coaxial cavity in said body between said motor and main cutting head and extending radially beyond the core-receiving recess in the latter, a supplemental core-removing bit rotatable by said motor and lying in said cavity in eccentric relation to the axis of the core-receiving recess, with its radial boundary overlying the axis of the latter, means for admitting fluid under pressure to the motor chamber for operating the motor, and fluid discharge means from the chamber to said cavity, whereby said fluid is discharged adjacent the cutting surfaces of the bit.

2. A rotary drilling unit comprising a main cutting head having a central core-receiving recess at its cutting end, forming an annular cutting portion, a connecting shank secured to said head by an intervening cylindrical body portion, a fluid-actuated motor housed in said body portion, a coaxial cavity in said body portion between said motor and main cutting head and extending radially beyond the core-receiving recess in the latter, a supplemental core-removing bit rotatable by said motor and lying in said cavity in eccentric relation to the axis of the core-receiving recess, with its radial boundary overlying the axis of the latter, a fluid inlet to said motor and a fluid outlet therefrom, the latter communicating with said coaxial cavity, whereby fluid is discharged adjacent the cutting surfaces of said head and supplemental bit.

3. A rotary drilling unit as claimed in claim 2, wherein said fluid-actuated motor comprises a gear motor, said supplemental bit being operatively connected to one of the gears thereof.

4. A rotary drilling unit as claimed in claim 3, wherein said supplemental core-removing bit consists of a grinding wheel mounted on a spindle of one of said gears.

5. A rotary drilling unit as claimed in claim 4, wherein said last-named gear is provided at its upper end with a thrust bearing.

6. A rotary drilling unit as claimed in claim 2, wherein the cutting face of said main cutting head is provided with a series of fluid passageways arranged in communication with said coaxial cavity.

7. A rotary drilling unit as claimed in claim 6, wherein said passageways radiate from the central core-receiving recess.

8. A rotary bit comprising a connecting shank, a cylindrical body secured to said shank and depending therefrom, a main cutting head carried by the lower extremity of said body and having a central core-receiving recess at its cutting end, forming an annular cutting portion, a chamber in said body, at least two longitudinally disposed, elongated meshing gears in said chamber, upper and lower end plates in said chamber, forming bearings for the respective ends of said gears, a coaxial cavity in said body between the lower end plate and main cutting head and extending radially beyond the core-receiving recess in the latter, a supplemental core-removing bit secured coaxially to one of said gears and lying in said cavity in eccentric relation to the axis of the core-receiving recess, with its radial boundary overlying the axis of the latter, means for admitting fiuid under pressure to one side of said gear chamber for operating the gears, and fluid discharge means from the chamber to said cavity whereby said fluid is discharged adjacent the cutting surfaces of the bit.

9. A rotary bit as claimed in claim 8, wherein the cutting surface of said main cutting head is diamond-studded.

10. A rotary bit as claimed in claim 8, wherein the cutting face of said supplemental core-removing bit is diamond-studded.

11. A rotary bit as claimed in claim 8, wherein the dimensions of the gears are such as to effect a surface speed of the grinding gear which is slightly greater than the surface speed of the periphery of the main cutting head, when a normal amount of fluid is being circulated through the gear motor.

12. A self-contained drilling .tool comprising a main cutting head, rotatable about a first axis and having a central core-receiving recess at its cutting end, forming an annular cutting portion, 2.)

a cavity in said main cutting head, a supplemental core-removing bit rotatably mounted in said cavity about a second axis, eccentric with respect to said first axis, the radial boundary of said supplemental bit lying within the radial confines of the cutting portion of said main cutting head, and extending radially across the core-receiving recess in the latter, at least to the center thereof, and fluid-actuated means for operating said supplemental bit.

13. A tool as claimed in claim 12, wherein said first and second axes lie parallel but in laterally spaced relation.

14. A tool as claimed in claim 12, including means for discharging said bit-operating fluid adjacent the cutting surfaces of said main cutting head and supplemental bit.

ARMAIS ARUTUNOFF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,034,073 Wright Mar. 17, 1936 2,497,144 Stone Feb. 14, 1950 2,587,429 Arutunoff Feb. 26, 1952 

